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Cellulosic fibers obtained from Barley straw were utilized to reinforce PHB. Four different processed fibers were employed as reinforcing material: sawdust (SW), defibered (DFBF), delignified (DBF), and bleached (BBF) fibers. The composite was processed from two different perspectives: a discontinuous (bach) and an intensification process (extrusion). Once processed and transformed into final shape specimens, the materials were characterized by mechanical testing (tensile mode), scanning electron microscopy, and theoretical simulations by finite elements analysis (FEA). In terms of mechanical properties, only the elastic moduli (Et) exhibited results ranging from 37% to 170%, depending on the reinforcement composition. Conversely, strengths at break, under both tensile and bending tests, tended to decrease, indicating poor affinity between the components. Due to the mechanical treatment applied on the fiber, DFBF emerged as the most promising filler, with mechanical properties closest to those of neat PHB. DFBF-based composites were subsequently produced through process intensification using a twin-screw extruder, and molded into flowerpots. Mechanical results showed almost identical properties between the discontinuous and intensification processes. The suitability of the material for agriculture flowerpots was demonstrated through finite analysis simulation (FEA), which revealed that the maximum von Mises stresses (5.38 × 105 N/m2) and deformations (0.048 mm) were well below the limits of the composite materials. [ABSTRACT FROM AUTHOR]

In recent decades, interest in oxide nanomaterials with multifunctional properties has grown significantly. Titanium dioxide undoubtedly belongs to them, characterized by exceptional photocatalytic activity, non-toxicity, high availability, biocompatibility, antibacterial properties, and low cost. The treatment of textile materials with TiO2 nanoparticles is relatively simple, but the insufficient bonding efficiency between certain fibers and TiO2 nanoparticles creates a problem regarding the stability and durability of the nanocomposites. In this study, an attempt was made to improve the properties of cotton modified with gelatin hydrogel, which was cross-linked by glutaraldehyde, and incorporated titanium nanoparticles. Three modification methods were applied, varying the mixing regimes of the components and the conditions. The composite materials were investigated via SEM, FTIR, UV-Vis and elemental analysis. For the first time, titanium nanoparticles obtained by the reduction of TiO2 with oxalic acid were used to modify cotton. Cotton samples were modified with gelatin hydrogel cross-linked with glutaraldehyde to increase the active groups of cellulose fibers that bind to Ti ions. Using the hydrogel, the nanoparticles are deposited on the surface of the textile substrate. The elemental analysis shows the presence of TiO2 nanoparticles. Lines for Ti atoms appear, which is evidence that the particles retain their composition after immobilization. Microscopic analyzes showed that TiO2 nanoparticles were distributed unevenly in the cotton matrix. In the UV analysis, the appearance of a new absorption at 890 cm-1 was observed due to the attachment of Ti-NPs. The appearance of the IR peak at 878 cm-1 confirms the formation of chelate complexes of the nanoparticles in the composite material. [ABSTRACT FROM AUTHOR]